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Spectroscopic Measurement Of The Electron Temperature In The Tenuous Argon Ion Laser Plasma, Dane Danijel Bicanic Apr 1971

Spectroscopic Measurement Of The Electron Temperature In The Tenuous Argon Ion Laser Plasma, Dane Danijel Bicanic

Physics Theses & Dissertations

The validity of the line intensity ratio technique for measuring the electron temperature was examined for an argon plasma with a "population inversion" i.e., the number of ions with electrons in the upper 4p levels was greater than in the lower 4s levels. The line intensities from these levels, the argon ion lasing transitions, were measured in a pulsed tenuous plasma at 110μ Hg produced by discharging a capacitor through a tube 2m long and 7mm inside diameter. The electron impact cross sections for simultaneous excitation and ionization as measured by Latimer and St. John were used and averaged over …


An Experimental Investigation Of The Vortex Sink Rate Sensors, Nelson L. Lu Apr 1971

An Experimental Investigation Of The Vortex Sink Rate Sensors, Nelson L. Lu

Mechanical & Aerospace Engineering Theses & Dissertations

The vortex sink rate sensor device consists basically of an ideal sink flow between two coaxial disks. A sink tube was located at the center of one disk. The vortex was created by the rotation of the unit about its axis of symmetry. Five inch and 10 inch diameter of porous couplers were used for the air chamber here in this investigation. Several slenderness parameters, i.e., the ratio of the sink tube diameter to the height of the air chamber ro/n were conducted. Two probes were used to measure the static pressure and stagnation pressure respectively at various positions …


Photoionization Of Photoexcited Cesium, Robert E. Hebner Jan 1971

Photoionization Of Photoexcited Cesium, Robert E. Hebner

Doctoral Dissertations

"A new method for obtaining the cross section for photoionization of photoexcited cesium is presented. The salient feature of this experiment is to use three crossed beams, i.e., two light beams intersecting a beam of cesium atoms. The cross section is determined by counting the ions produced by the two step process: Cs (6S) + h[upsilon]₁ --> Cs (6P) ; Cs (6P) + [upsilon]₂ --> Cs⁺ + e⁻ The relative cross section for the second step has been obtained from threshold (5060 Å) to 2500 Å. The excitation light source used in obtaining this cross section was a rf resonance …


Interplanar Force Constants Of Symmetry Planes In Close-Packed Structures, Paul G Khoury Jan 1971

Interplanar Force Constants Of Symmetry Planes In Close-Packed Structures, Paul G Khoury

Archived Theses and Dissertations

No abstract provided.


Scattering Of Waves In Many Dimensions, I. Adawi Jan 1971

Scattering Of Waves In Many Dimensions, I. Adawi

Physics Faculty Research & Creative Works

Scattering by a spherical potential is discussed in all dimensions by one formulation using the partial-wave expansion method. The optical theorem relating the total scattering cross section σ to the forward scattering amplitude f(0) is derived.


Calculation Of Anisotropic Hyperfine Constants For Lattice Nuclei Near A Shallow Donor, Edward B. (Boyd) Hale, Robert Lee Mieher Jan 1971

Calculation Of Anisotropic Hyperfine Constants For Lattice Nuclei Near A Shallow Donor, Edward B. (Boyd) Hale, Robert Lee Mieher

Physics Faculty Research & Creative Works

A method is presented for calculating the magnetic anisotropic (dipolar) hyperfine constants for lattice nuclei near a shallow-donor impurity. The method assumes that the wave function of the donor electron can be expressed in an effective-mass form, i.e., a slowly varying envelope function times conduction-band Bloch functions. For each dipolar hyperfine constant, two separate calculations are performed. One calculation is for a local region about the lattice nucleus of interest. The greatest part of the interaction occurs in this region (about 85 ± 10%). The second calculation is for the more distant region. The dipolar constants in the distant region …


Second- And Third-Order Elastic Constants Of Aluminum And Lead, Tetsuro Suzuki Jan 1971

Second- And Third-Order Elastic Constants Of Aluminum And Lead, Tetsuro Suzuki

Physics Faculty Research & Creative Works

The second- and third-order elastic constants of Al and Pb are calculated as the second and third derivatives of the binding energy with respect to the finite deformation parameter. The binding energy is derived from a local pseudopotential by use of second-order perturbation theory. It is shown that the binding energy satisfied not only the diagonal equilibrium condition, but also the off-diagonal equilibrium condition, i.e., the first derivative of the binding energy with respect to a volume change as well as with respect to shear deformations is zero. Accordingly, the present method of calculation is based on a stable lattice …


Theory Of Nucleation Of Water Properties Of Some Clathrate Like Cluster Structures, Mehdi Daee Jan 1971

Theory Of Nucleation Of Water Properties Of Some Clathrate Like Cluster Structures, Mehdi Daee

Doctoral Dissertations

"The tranquility of classical homogeneous nucleation theory has been disturbed by the introduction of statistical mechanical correction factors to a basically thermodynamic theory. These factors, which appear to be essential, destroy much of the agreement with experiment in the case of water vapor. A molecular model for the pre-nucleation water clusters is proposed with a view toward resolving some of these difficulties. As a first step, the Properties of a few specific cluster configurations have been examined. Clathrate-like structures containing 16 to 57 water molecules are discussed. The hydrogen bonds were treated as simple harmonic oscillators for the purpose of …


Homogeneous Nucleation Of Water Vapor In Inert Gas Atmospheres, Arthur Henry Biermann Jan 1971

Homogeneous Nucleation Of Water Vapor In Inert Gas Atmospheres, Arthur Henry Biermann

Doctoral Dissertations

"The homogeneous nucleation of water vapor in atmospheres of helium, neon, argon, krypton, and xenon was studied using an expansion type cloud chamber. A strong dependence of the nucleation rate on the particular inert carrier gas was observed. At present the only dependence upon the nature of the carrier gas included in classical nucleation theories is a small factor arising from kinetic considerations which is in the wrong direction to explain the observations. To explain the dependence of the rate on the nature of the carrier gas, a molecular cluster model is assumed allowing inert gas atoms to occupy the …


Are There Magnetic Moments At The Transition Metal Sites In Feal, Coal, And Nial?, Richard B. Frankel, D. J. Sellmeyer, N. A. Blum Sep 1970

Are There Magnetic Moments At The Transition Metal Sites In Feal, Coal, And Nial?, Richard B. Frankel, D. J. Sellmeyer, N. A. Blum

Physics

Measurements of the hyperfine interactions in 57Fe in the CsCl structure intermetallic compounds FeAl, CoAl and NiAl are reported.


Investigation Of The Alpha-Sub-Gamma Phase In Alnico 6, Cortez Samuel Sep 1970

Investigation Of The Alpha-Sub-Gamma Phase In Alnico 6, Cortez Samuel

Dissertations and Theses

The purpose of this research project was to study the αᵧ phase in Alnico 6. Other phases were studies for comparison. Also the effect of an applied magnetic field on the formation of the αᵧ phase was investigated.

Three single crystals of Alnico 6 were heat treated for one hour--one at 1250°C, one at 1000°C, and one at 800°C--and water-quenched. The microstructure of each sample was observed with the optical microscope, and X-ray diffraction patterns were taken to determine the crystal structure of the phases present.

Several single crystal samples of Alnico 6 were heat treated at 1000°C and furnace-cooled. …


De Haas-Van Alphen Effect In Dilute Beryllium-Copper Alloys , I.S. Goldstein, David J. Sellmyer, B.L. Averbach Sep 1970

De Haas-Van Alphen Effect In Dilute Beryllium-Copper Alloys , I.S. Goldstein, David J. Sellmyer, B.L. Averbach

David Sellmyer Publications

The de Haas-van Alphen effect was investigated in pure beryllium and in Be-Cu alloys containing up to 0.34 at.% Cu. The extremal cross-sectional areas of the cigar-shaped third-band electron pieces of Fermi surface decreased with alloying. The areas of the coronet-shaped second-band hole piece increased with alloying. The magnitude of the area changes were compared with rigid-band-theory predictions. Corrections for lattice-parameter changes were included when possible. In the low-concentration limit, the theory is able to account for the observed area changes. For the highest-concentration alloy, there are deviations, for all areas measured, to greater changes than are predicted by the …


12th Annual Rocky Mountain Spectroscopy Conference Aug 1970

12th Annual Rocky Mountain Spectroscopy Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 12th annual meeting of the Rocky Mountain Spectroscopy Conference, sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 3-4, 1970.


The 1963-64 Lake Mead Survey, J. M. Lara, J. I. Sanders, Bureau Of Reclamation Aug 1970

The 1963-64 Lake Mead Survey, J. M. Lara, J. I. Sanders, Bureau Of Reclamation

Publications (WR)

The 1963-64 Lake Mead survey was run to compute the reservoir capacity. Results of the geodetic and hydrographic surveys and sediment sampling equipment are described. The geodetic survey showed Hoover Dam subsided an average of 118 mm since 1935. Sonic sounding, photogrammetry, and crosssectional profiling methods were used to run the hydrographic survey. Reservoir area and capacity tables were generated using an electronic computer. The present lake capacity is 29,755,000 acre-ft and the reservoir surface area is 162,700 acres at elevation 1229 ft. 2,720,000 acre-ft of sediments accumulated in the lake since 1935. A unit weight of 60 Ib/cu ft …


Electron Optical Study Of A Secondary Electron Multiplier, Chang Min Shen Jul 1970

Electron Optical Study Of A Secondary Electron Multiplier, Chang Min Shen

Dissertations and Theses

Electron orbital theory was applied to the design of the geometrical structure of an electron multiplier for an image intensifier. A special structure satisfying production requirements was studied. Electron optical calculations consisted of determining the potential distribution and tracing the electron trajectories. Liebmann's procedure was used to solve Laplace's equation with constant potentials on the multiplier electrodes as boundary conditions. The trajectories were determined by solving the equation of motion in an electrostatic field using a Runge-Kutta procedure. The initial conditions for the trajectories were the initial energies, initial positions, and the initial directions of the secondary electrons. The plotted …


Determination Of (N, 2n) Reaction Cross-Sections For 71ga, 106cd & 138ba Using 14 Mev Neutrons, Thomas Helm Jul 1970

Determination Of (N, 2n) Reaction Cross-Sections For 71ga, 106cd & 138ba Using 14 Mev Neutrons, Thomas Helm

Masters Theses & Specialist Projects

The increasing trend towards the use of activation analysis as an analytic means of identifying elements and determining their relative abundance demands more accurate values of reaction cross-sections. Accurate values of cross-sections are also important in the investigation of possible shell effects in reaction mechanisms. Many activation cross-sections for reactions produced by 14 MeV neutrons have been measured because of the relative ease with which this energy of neutrons can be produced. Low voltage accelerators are capable of producing 14. MeV neutrons by the 3H( d,n)4He reaction. Although many people(1-5) have measured the (n,2n) reaction cross-sections …


A Numerical Solution To The Problem Of Rotation Near The Ground, David D. Chen Jul 1970

A Numerical Solution To The Problem Of Rotation Near The Ground, David D. Chen

Mechanical & Aerospace Engineering Theses & Dissertations

No abstract.


An Investigation Of A Gas Measurement Technique Employing Ultraviolet Excitation, Alphonso Vincent Diaz May 1970

An Investigation Of A Gas Measurement Technique Employing Ultraviolet Excitation, Alphonso Vincent Diaz

Physics Theses & Dissertations

A study was undertaken to determine the general applicability of a temperature measurement technique which uses the fluorescence stimulated by a vacuum ultraviolet continuum as the indicator. This study was directed toward determining the temperature of nonradiating carbon monoxide. A number of ultraviolet radiation sources which produced high intensity in the region of l,150 A were investigated. This study led to the conclusion that the technique was not applicable to measurements in carbon monoxide within the present limits of' detectability.


Response Of Nuclear Emulsion To Electron Beams, Robert Katz, E. J. Kobetich Jan 1970

Response Of Nuclear Emulsion To Electron Beams, Robert Katz, E. J. Kobetich

Robert Katz Publications

A recent theory of particle tracks assumes that the probability P for grain development in nuclear emulsion depends on the local dose E of ionization energy deposited by secondary electrons (delta rays) in the neighborhood of the particle track. The response is assumed to be one of exponential survival; that is, if E0 is the dose for 37% survival, then P = 1 – exp (-E/E0). By calculation of the dose E(t) deposited at depth t in the emulsion by normally incident, monoenergetic electron beams, and applying the assumed dose-effect relationship, …


Optical Phenomena In Diatoms, Richard B. Hoover, Miriam J. Hoover Jan 1970

Optical Phenomena In Diatoms, Richard B. Hoover, Miriam J. Hoover

Journal of the Arkansas Academy of Science

Diatoms are unicellular algae which fabricate siliceous shells that are frequently marked with intricate ornamentations and patterns. The nature and characteristics of the siliceous shells provide a basis for diatom taxonomy and give rise to a number of interesting and colorful optical phenomena. This paper presents the results of investigations of diffraction phenomena, complementary color behavior, Rayleigh scattering and optical activity in diatoms.


(02) The Papers Of Robert H. Goddard, Volume I: [1927 And 1933: Material For An Autobiography], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(02) The Papers Of Robert H. Goddard, Volume I: [1927 And 1933: Material For An Autobiography], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section contains material for an autobiography written by Robert Goddard in 1927 with interpolations in 1933.

Disclaimer: The images in these scans have been rendered somewhat distorted after the fact. We apologize for this error. Thankfully, most of the photographs used in these …


(06) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1921-1924: Beginnings Of Experimentation With Liquid Propellants], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(06) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1921-1924: Beginnings Of Experimentation With Liquid Propellants], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from 1921 through 1924. During this time, Goddard began his experimentation with liquid propellants for rockets, became a part-time consultant on solid-propellant rocket weapons for the U.S government, began a twenty-year tenure as Director of Physical Laboratories at …


(04) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1898-1914: Speculation And Preparation], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(04) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1898-1914: Speculation And Preparation], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from age sixteen through thirty-two. It contains diary entries, correspondence, school themes, entries from his green notebooks (used for calculations), a graduation oration, published articles,

This section contains the following articles:
"The Use of the Gyroscope in the Balancing and …


(10) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1932-1934: Interlude At Clark University], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(10) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1932-1934: Interlude At Clark University], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers a brief period in Robert Goddard's life, from mid 1932 to mid 1934, between his two grant funded periods (1930-1932, 1934-1942) for rocket research in Roswell, New Mexico. During this time, he continued to teach at Clark University and conduct research …


(13) The Papers Of Robert H. Goddard, Volume Iii: 1938-1945 [1938-1941: Rockets With Turbopumps], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(13) The Papers Of Robert H. Goddard, Volume Iii: 1938-1945 [1938-1941: Rockets With Turbopumps], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers 1938 to 1942. During this period, Goddard begins to develop turbine-driven pumps for liquid propellant rockets and conducts a series of flight tests with pump-driven rockets.

This section contains correspondence by, to, and about Robert H. Goddard from the following people and entities: …


(05) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1915-1920: Experimentation With Solid Propellants], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(05) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1915-1920: Experimentation With Solid Propellants], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from 1915 through 1920. During this time, he became an Assistant Professor in Physics at Clark University, demonstrated that reaction takes place in a vacuum, hence a rocket could function in airless space, received his first Smithsonian grant …


(08) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1925-1930: Liquid-Propellant Rockets Fly], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(08) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1925-1930: Liquid-Propellant Rockets Fly], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from 1925 through the middle of 1930. During this time, Goddard achieved his greatest success on March 16, 1926, with the first ever flight of a liquid-propellant rocket. This period also saw a 1929 flight that attracted a …


(01) The Papers Of Robert H. Goddard, Volume 1: 1898-1924 [Forward, Introduction], Esther C. Goddard, G. Edward Pendray Jan 1970

(01) The Papers Of Robert H. Goddard, Volume 1: 1898-1924 [Forward, Introduction], Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section contains a forward by G. Edward Pendray and an introduction by Esther C. Goddard.

Disclaimer: The images in these scans have been rendered somewhat distorted after the fact. We apologize for this error. Thankfully, most of the photographs used in these papers …


(14) The Papers Of Robert H. Goddard, Volume Iii: 1938-1945 [1941-1945: Jato And Variable Thrust For The Military], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(14) The Papers Of Robert H. Goddard, Volume Iii: 1938-1945 [1941-1945: Jato And Variable Thrust For The Military], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers the final years of Robert Goddard's life, from 1941 to 1945. During this time, he became the Director of Research for the Bureau of Aeronautics, Navy Department, at Annapolis, Maryland, developing variable-thrust rocket motor later used on Bell X-2 rocket plane. He also …


(11) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1934-1937: Return To New Mexico; Pressure-Tank Rockets], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray Jan 1970

(11) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1934-1937: Return To New Mexico; Pressure-Tank Rockets], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from mid-1934 through 1937. During this time, Robert and Esther Goddard began their second stint in Roswell, New Mexico for Guggenheim funded rocket research (the first was 1930 to 1932). This one would last from 1934 to 1942. …